NOTE: I find it best to work with a blue, yellow, or green car. It's a pain with a red car, especially a maroon one, because it'll typically end up looking like wood, believe me, I've already learned my lesson. Other colors I'm sure it'll work, but I haven't tested them. Also, this is a very tedious and long project. In fact, it took me around 3 hours to do this toon, so make sure you have some free time on your hands. And yes I know, a better and easier effect can be achieved in Illustrator; this is an alternative and achievable through Photoshop, so don't bother me about it. Also, the pen tool may be used, I just didn't feel the need to explain the technique, but if you're familiar with the pen tool, by all means, use it instead of the line tool if you feel the need.
1. Start with your picture, probably one that is full of reflections (it'll look better in the end because it will be more elaborate.
2. Make any modifications that you want to in the image right now. It's a best bet to shave the door handles and the emblems, because they are a pain to cel-shade.
3. Make sure you select the line tool and set it at black and start outlining the car, the panels, and the major reflections. Like the picture below. You can add the lines on a different layer if you'd like, but I did not choose to...
4. Then select the Polygonal Lasso Tool and select an area between the black lines that you made. The selection shouldn't be exact, infact it is better to be a little rough because it will all eventually blend in. Just make sure you're in between the black lines that you made.
5. Select the eyedropper tool, and sample a color within that area of your selection and fill it with the paintbucket. If you do not know where the paintbucket is, it is under the gradient tool, just right click and it should reveal the paintbucket tool. Alternatively, you can press ALT+Backspace, and it'll fill it just fine.
Just repeat this to the other parts of the car. Here's a look at the cel-shading in process. You might want to make the windows black, it'll save you a lot of time. Also I used a gradient for the side windows because the original windows looked similar to that. Make sure to zoom out once in a while, and make sure everything looks right.
Headlights, rims, and wheels can also be done, but they require an even higher amount of patience to cel-shade. I omitted the headlights and wheels for the sake of time, but in reality they aren't that hard. Here's the final result. When you save as a jpeg, go to File>Save for Web and put the quality at whatever you want, preferably the highest, and set the blur to 0.5, it'll produce a nicer result without as many jagged edges.







More Photoshop: